Complex Regional Pain Syndrome (CRPS): A Screening & Treatment Update motor or tropic changes The updated criteria weeds out outlier diseases, added Dr. Harden. ''When we tried to use the Budapest criteria as an entry into research, I have to say all heck broke loose.” There have been several trials that have failed, most likely because CRPS is a multifactorial, multi-mechanism disease. So the treatments under study are not likely to produce results with a significant P value because the population studied has different mechanisms underlying the disease. He said that the Budapest criteria ...